Pre-requisites:

- During the scrubbing run the interlock threshold on the temperature of the MKE kickers should be ~ 90º C (it should be ~ 70º C when there are extractions) => Call Etienne Carlier to check and change it if necessary

- During the scrubbing run and the LONG MDs with LHC beam the ZS are RETRACTED / HV to 0 kV / ION TRAPS ON (inform the ZS expert). The cooling circuit for the septa magnets (circuits 214, 414 and 614) should be switched OFF (by TI). Block the fast vacuum valves OUT in the injection and extraction areas (LSS1, LSS2, LSS6)

Monday 09/06 (08:00 - 16:00) - Injector technical stop

Monday 09/06 (16:00) until Thursday 12/06 (08:00) - SPS scrubbing run => We will run always with nominal (or above nominal if possible) bunch intensity. The number of batches will increase from 1 to 4 (and may be 6) during the scrubbing run. In all the cases we will vary the amount of time the beam spends in the machine by playing with the timing of the beam dump. There will be no coast this year to study the beam lifetime due to the much shorter scrubbing run (2.5 days) compared to the previous years (~ 1 week)

Beam conditions: LHC in SPS on Scrubbing Cycle (SCRUB_PDOT_V1 - 43.2 s long)

N_b = 1.3 x 10¹¹ p/b

Transverse emittances: e^* £ 3 mm

Longitudinal emittance: e_L^* = 0.35 eV.s

Participants for the beam set up: OP, RF, ABP

During the scrubbing run many ecloud related measurements will be performed in particular with the new equipments installed from 514 to 518: AB/ABP-OP-RF, AT/VAC and TS/MME

Monday 09/06 (16:00 - 22:00)

Setting-up of Injection and Capture of the 25 ns LHC beam

Injection (kicker timing adjustment)

Tune and chromaticity measurement and adjustment

#batches = 1 (12 bunches)

Verify that following measurements work:

• BCT
• Fast BCT => Data should be stored every cycle
• LHC BPM (bunch-by-bunch position measurement)
• Longitudinal bunch profile along the batch from the Faraday cage => Data should be stored every hour
• Wire scanner (51995) => Data should be stored every hour
• IPMs => If available it would be good to have it running and storing data all the time
• Head Tail Monitor
• E-cloud monitors
• Kickers temperature and vacuum (in particular MKEs and MKDV)
• Vacuum => Faster vacuum logging in the vacuum gauges in LSS5

Monday 09/06 (22:00) - Tuesday 10/06 (04:00)

Check injection (kicker timing adjustment)

Feedforward and longitudinal feedback setting-up

Check transverse dampers

#batches = 1 (72 bunches) (watch the vacuum!!!)

Tuesday 10/06 (04:00 - 09:00)

Scrubbing run

#batches = 1 (72 bunches)

Tuesday 10/06 (09:00 - 12:00)

Setting-up for multiple injections (from 2 to 4 and may be 6)

#batches = 1-4 and may be 6 (the number of batches will be maximized compatibly with the MKE heating and the vacuum initially, keeping the maximum duty factor)

Call BT expert (Etienne Carlier) to do the fine synchronization of the injection kickers

Tuesday 10/06 (12:00) - Thursday 12/06 (08:00)

Scrubbing run

#batches = 1-4 and may be 6 (the number of batches will be maximized compatibly with the MKE heating and the vacuum, keeping the maximum duty factor)

Thursday 12/06 (08:00 - 09:00) - End of the scrubbing run and recovering (SPS supercycle = SFT-CNGS-LHCFAST2_V2)

Unblock the vacuum valves in the injection and extraction areas

Ask TI to restart the cooling circuit for the septa magnets (circuits 214, 414 and 614)

J. Borburgh should verify the conditioning of the septa

L. Ducimetiere and Viliam Senaj should verify the conditioning of the MKDV

Author: Elias Métral - AB/ABP
Last update: Wednesday, June 11, 2008 02:33:04 PM
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